Month: November 2016

We are seeking to appoint an exceptional candidate to the position of Postdoctoral Research Fellow to work on a unique new project “Adaptation and resilience of coral reefs to environmental change in Singapore” hosted at the National University of Singapore, and funded by Singapore’s National Research Foundation (NRF). This is a 4.5-year interdisciplinary research project comprising multiple themes represented by teams with extensive expertise in coral biology, experimental ecology, palaeontology, geochemistry and microbiology.

The Research Fellow will lead the sub-project to investigate the evolutionary, ecological and population genetic history of corals in Singapore. Candidate with a PhD degree and prior research experience in marine field research and molecular biology using next-generation sequencing tools (e.g. DNA hybridisation capture, RNA-seq, RAD-seq) is required. Rescue SCUBA diver preferred.

This is a full-time position over two years, with possible extension. Remuneration will be commensurate with the candidates’ qualifications and experience. Please address enquiries to huangdanwei@nus.edu.sg

Full-time Research Assistant – Understanding Fire Activity in Indonesia
Asian School of the Environment, Nanyang Technological University (apply by 31st January 2017)

The successful applicant will assist in a study to understand the patterns of fire activity in Indonesia. This would include conducting literature reviews of relevant articles and information, managing a database to include geospatial and socioeconomic datasets related to the drivers of fires in Indonesia, and also organise and conduct field work to collect new data. The successful applicant will be required to visit the field and conduct interviews with local communities or representatives of non-governmental organizations to understand land conflicts in Indonesia. This is a full-time (1 year) position. The candidate will work closely with the principal investigator.

Job responsibilities:

Literature review and data compilation of land conflicts in Indonesia

Geospatial analysis of forest loss and degradation in Indonesia

Coordinate and manage ecological and social datasets

Field trips to non-governmental organizations in Indonesia and conduct interviews with local representatives from NGOs or communities

Interested applicants should submit a cover letter explaining why they are interested in this position and how this may help them in their future career, and their CV specifying their software knowledge, research experience and two referees. Please submit these two documents to janicelee@ntu.edu.sg. Only successful applicants will be contacted for interviews. The closing date for this application is 31st January 2017.

PhD graduate Maxine Mowe, now a research fellow at the Freshwater and Invasion Biology Lab, discusses juggling research and teaching during her graduate studies in the New Eurasian magazine, Oct-Dec 2016 issue.

The ornamental pet trade is often considered a key culprit for conservation problems such as the introduction of invasive species (including infectious diseases) and overharvesting of rare species. Here, we present the first assessment of the biodiversity of freshwater molluscs in the ornamental pet trade in Singapore, one of the most important global hubs of the ornamental aquarium trade, and discuss associated conservation concerns. We recorded freshwater molluscs from ornamental pet shops and major exporters including non-ornamental species (e.g., hitchhikers, molluscs sold as fish feed).

We recorded an unexpectedly high diversity—59 species—of freshwater bivalves and gastropods, with the majority (38 species or 64%) being from the Oriental region. In addition to morphological examination, we sequenced the DNA barcode region of mitochondrial CO1 and 16S genes to provide molecular data for the confirmation of the identification and for future re-identification. DNA barcodes were obtained for 50 species, and all but four were separated by > 3% uncorrected pairwise distances.

The trade has been considered a main introduction pathway for non-native species to Singapore, and we found that out of 15 species in the trade as well as in the wild in Singapore, 12 are either introduced or of unknown origin, representing almost half of the known non-native freshwater molluscs in Singapore. Particularly prevalent are non-ornamental species: six hitchhikers on aquarium plants and six species sold as fish feed. We found that a quarter of the trade species have a history of introduction, which includes 11 known or potentially invasive species. We conclude that potential overharvesting is difficult to assess because only half of the trade species have been treated by IUCN. Of these, 21 species are of Least Concern and three are Data Deficient.

Our checklist, with accompanying DNA barcodes, images, and museum vouchers, provides an important reference library for future monitoring, and constitutes a step toward creating a more sustainable ornamental pet trade.

Abstract – Freshwater snails (Gastropoda) in Southeast Asia are among the most diverse aquatic groups. Like freshwater molluscs globally, they are threatened by, among other things, aquatic invasive species. Fourteen gastropod species have been introduced in Southeast Asia, including globally-invasive and cryptogenic species (of unknown origin), with Singapore having the highest number (23 species). Freshwater gastropods in Singapore are almost exclusively found in urban habitats, including human commensal native species suspected to have been introduced. Clarifying the status of these and other poorly-known freshwater gastropods can help to prioritise conservation and management efforts of native and invasive species, respectively. My thesis therefore aims to examine the origins and potential impacts of introduced freshwater gastropods in Singapore.

I began with a morphological and molecular study of freshwater mollusc diversity in the ornamental pet trade, the key introduction pathway for aquatic organisms in Singapore. Fifty-nine species (most from the Oriental region) were recorded in the trade, accounting for almost half of known introduced freshwater molluscs in Singapore, including the globally-invasive New World apple snails, Pomacea spp. (Ampullariidae). This led me to investigate the Ampullariidae in Singapore, and I confirmed the establishment of two superficially similar South American species, Pomacea canaliculata and Pomacea maculata. Surprisingly, the purportedly native Pila scutata, was found to be a human commensal, and probably introduced to Singapore instead (further reinforced by demonstrated resistance to anthropogenic habitat disturbance in subsequent stable isotope studies).

To resolve this, I then surveyed Pila scutata in Peninsular Malaysia and Singapore to investigate its distribution and genetic diversity. I found that Pila had been displaced by Pomacea at most historical sites. Only one Pila scutata population in Malaysia and six in Singapore were found, with all individuals sharing a single haplotype—further strong evidence that these populations were introduced by humans.

Pila nevertheless remains a native Southeast Asian genus, so I investigated the potential impacts of South American Pomacea on Pila in terms of feeding ecology. Stable isotope analysis showed no resource overlap between these taxa in habitats where they co-occur, while ex-situ experiments comparing feeding rates indicated that Pomacea feeds more quickly than Pila. My results indicate that Pila may be able to persist at sites where it is syntopic with Pomacea, but further studies are required to understand the interactions between the taxa.

Though my study mostly focussed on apple snails, non-ampullariids, constituting > 80% of Singapore’s introduced gastropods, are also important components of the ecosystem that should not be overlooked. In the course of this study, I clarified the confused taxonomy of two long-established species, Sinotaia guangdungensis (Viviparidae) and Physa acuta (Physidae), and reported two new records of introduced species, Pyrgophorus platyrachis (Cochliopidae) and Anentome helena (Nassariidae). Based on my study, the number of freshwater mollusc species in Singapore is now updated to 4 native, 15 introduced, and 10 cryptogenic.

Overall, this thesis provides, for the first time, important baseline information and further research directions on various aspects of introduced freshwater molluscs in Southeast Asia, which are more widespread than previously thought.